The invention relates to a method of photolithographically treating a substrate, in which a surface of the substrate, at least at the area at which the substrate consists of an inorganic material, is treated with an organosilicon compound in order to improve the adhesion of a photolacquer layer to be applied to the substrate.
In photolithographic process, after exposure and development of an applied photolacquer layer when using, for example, the developed photolacquer layer as an etching mask, patterns are etched into the substrate, or when using the developed photolacquer layer as an application mask for a substrate, a structure is applied to the part of the surface of the substrate not covered by the photolacquer layer with the aid of a so-called lift-off process.
A frequent problem in photolithographic treatments is unsatisfactory adhesion of the photolacquer layer to the substrate. This problem is the more serious as the patterns and structures to be manufactured have smaller dimensions, for example, dimensions of 1.5 .mu.m, as have become usual in the modern semiconductor industry.
In order to improve the adhesion of the photolacquer layer, substrate are frequently pretreated with so-called primers, for example, an organosilicon compound, such as a chlorosilane. Silanes of this type, however, hydrolyse readily, while in the presence of moisture they form polycondensation products which are distributed irregularly over the surface, as a result of which the ultimate pattern definition is disturbed and it is difficult to remove the polycondensation product from the surface in a homogeneous manner.
The usual primers are moreover toxic and corrosive.